.panel.panel-default
    .panel-heading
        h3.panel-title 最受欢迎
    .panel-body
        each img in popular
            .col-md-4.text-center(style='padding-bottom: .5em;')
                a(href=`/images/${img._id}`)
                    img.img-thumbnail(src=`/upload/${img.filename}`, style='width: 75px; height: 75px;')
